The goal of this research is to increase the affordability and accessibility of hearing health care-a priority of the NIDCD/NIH. Of those who could benefit from hearing aid amplification, less than one in ten with mild hearing loss and less than four in ten with moderate-to-severe hearing loss acquire and use hearing aids. One of the most often reported reasons that people do not seek intervention is hearing aids' high cost. Currently a variety of low-cost hearing aids equipped with relatively low-end technologies are available on the market. Thus, it is important to examine if hearing-impaired elderly adults, who typically have fewer communication demands than younger listeners, need expensive high-end technologies to attain optimal hearing aid benefits. The first aim of this research is to investigae the relationship between technology level and the real-world effectiveness of hearing aids in elderly adults with bilateral mild to moderate hearing loss, focusing on directional microphone and digital noise reduction technologies. Because (1) the effects of these two hearing technologies are highly dependent on the listening situation and (2) elderly listeners are less able to correctly recall the situational-dependent effect after month-long field trials, we will employ a real-world outcome measure system that has sufficient situational resolution and is not subject to recall bias to assess real-world hearing aid effectiveness. The system consists of (1) a subjective Ecological Momentary Assessment, which involves repeated sampling of listeners' perception in real time and in natural environments using modern wireless smartphones and the Internet, and (2) an objective, automated system that could characterize and model the listeners' natural communication behaviors and environments by analyzing the audio recordings made during the listeners' daily activities. Since this system has not been used to evaluate hearing technologies, the second aim of this research is to explore how our outcome measure system, wireless smartphones, and the Internet could be used to determine the success of hearing health care. In each field trial section of the study, participants will wear hearing aids equipped with low- or high-end directional microphone and digital noise reduction technologies for four weeks and then use our outcome measure system to assess hearing aid success for one week. The benefits of the technologies will be examined and compared to determine the minimal technology level needed by elderly listeners, which in turn will facilitate more appropriate and affordable hearing health care. The feasibility, reliability, and compliance of our assessment system will also be examined. Such information will be valuable in the implementation of automated tele-audiology, which will greatly increase the accessibility of hearing health care.